Haworthiopsis koelmaniorum

Taxonomy
Scientific Name
Haworthiopsis koelmaniorum (Oberm. & D.S.Hardy) Boatwr. & J.C.Manning
Higher Classification
Monocotyledons
Family
ASPHODELACEAE
Synonyms
Haworthia koelmaniorum Oberm. & D.S.Hardy, Tulista koelmaniorum (Oberm. & D.S.Hardy) G.D.Rowley
National Status
Status and Criteria
Vulnerable A2acd; C2a(i)
Assessment Date
2014/03/17
Assessor(s)
L. von Staden, M. Lötter, J.E. Burrows & A. Biko'o
Justification
A highly localized species (EOO 389 km²), that has declined by at least 30% within one to two generations, primarily due to collecting for horticultural purposes, but also habitat loss and degradation. The population is estimated to consist of fewer than 4000 mature individuals, with none of the 10 known subpopulations numbering more than 1000 mature individuals, and decline continues.
Distribution
Endemism
South African endemic
Provincial distribution
Limpopo, Mpumalanga
Range
Groblersdal to Loskop Dam.
Habitat and Ecology
Major system
Terrestrial
Major habitats
Loskop Thornveld, Loskop Mountain Bushveld
Description
Bushveld, on sandstone outcrops and ridges.
Threats
Collecting of plants out of the wild for horticultural purposes is the main threat to this species, and has resulted in the local extinction of the type locality and the drastic reduction of population numbers in at least two other known subpopulations. There are also reports that it is collected for medicinal purposes (Crous 1984), however, the severity of the impact of medicinal harvesting is not currently known. Some subpopulations outside protected areas are subjected to poor fire management - vegetation is being burnt when this species is in flower, which will lead to poor reproductive output and declines in the long run, especially since many mature individuals are also being uprooted and eaten by small mammals (A. Biko'o, pers. obs.). One subpopulation was lost to expanding crop fields, and habitat degradation due to overgrazing and trampling on overstocked communally owned lands, as well as competition from alien invasive plants, are additional, but less severe threats.
Population

A detailed survey and monitoring of this species' narrow range indicate that there were about 10 subpopulations, with the subpopulation size ranging between 20 and 588 mature individuals, and with one subpopulation consisting of around 1000 mature individuals. Collecting has however drastically reduced the number of individuals in four subpopulations, and two are now suspected to be locally extinct, as plants could not be relocated in recent surveys. The population size is estimated to number fewer than 4000 mature individuals, and collecting has reduced the population by at least 30% within 30 years (1-2 generations).


Population trend
Decreasing
Notes
Rowley (2013) transferred Haworthia koelmaniorum and its varieties to Tulista. Manning et al. (2014) argued that it is better placed in Haworthiopsis, however, they neglected to make a new combination for Tulista koelmaniorum var. mcmurtryi. This assessment includes this taxon.
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Haworthiopsis koelmaniorum (Oberm. & D.S.Hardy) Boatwr. & J.C.ManningVU A2acd; C2a(i)2014.1
Haworthia koelmaniorum Oberm. & D.S.Hardy var. koelmaniorum VU A2acd; C2a(i)Raimondo et al. (2009)
Haworthia koelmaniorum Oberm. & D.S.Hardy var. mcmurtryi (C.L.Scott) M.B.BayerEN B1ab(iii,v)+2ab(iii,v)Raimondo et al. (2009)
Haworthia mcmurtryi C.L.ScottIndeterminate Hilton-Taylor (1996)
Haworthia mcmurtryi C.L.ScottIndeterminate Hilton-Taylor (1996)
Haworthia koelmaniorum Oberm. & D.S.Hardy var. koelmaniorum Vulnerable Hilton-Taylor (1996)
Haworthia koelmaniorum Oberm. & D.S.HardyRare Hall et al. (1980)
Bibliography

Bayer, M.B. 1999. Haworthia Revisited: A revision of the genus. Umdaus Press, Hatfield.


Bayer, M.B. 2003. Where to Haworthia limifolia? Aloe 40(2):41-51.


Crous, S.J. 1984. Haworthia koelmaniorum. Aloe 20(4):86-87.


Esterhuizen, J.M. 2001. Haworthia koelmaniorum (Oberm. & Hardy) and Haworthia mcmurtryi (Scott): Mpumalanga's contribution to the Genus Haworthia. Alsterworthia International 1(2):14-15.


Hall, A.V., De Winter, M., De Winter, B. and Van Oosterhout, S.A.M. 1980. Threatened plants of southern Africa. South African National Scienctific Programmes Report 45. CSIR, Pretoria.


Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.


Manning, J.C., Boatwright, J.S., Daru, B.H., Maurin, O. and Van der Bank, M. 2014. A molecular phylogeny and generic classification of Asphodelaceae subfamily Alooideae: A final resolution of the prickly issue of polyphyly in the Alooids? Systematic Botany 39(1):55-74.


Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. and Manyama, P.A. 2009. Red List of South African Plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.


Rowley, G.D. 2013. Generic concepts in the Alooideae. Part 3 - The phylogenetic story. Alsterworthia International Special Issue 10:1-6.


Citation
von Staden, L., Lötter, M., Burrows, J.E. & Biko'o, A. 2014. Haworthiopsis koelmaniorum (Oberm. & D.S.Hardy) Boatwr. & J.C.Manning. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2020/10/20

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Distribution map


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